Postural deformity is common among wheelchair users due to the tendency of the spine to flex under the influence of gravity. For individuals with paralysis of the trunk muscles, these postural deformities can occur quickly after injury and can reduce function and lead to painful fixed deformities. To delay the onset of these deformities, it is imperative that wheelchair seating be designed and prescribed which provides the necessary support to counteract gravity, but does not overly-restrict the users'ability to move their trunk so they can accomplish their daily activities. While sophisticated seating and position products for electric power wheelchair are on the market, advances for manual wheelchairs seating have focused on pressure relieving cushions. Rigid backrests are being marketed which replace the traditional sling designs are being marketed, and users'report an increased comfort over sling systems, but they have drawbacks which have limited their market penetration. The three primary drawbacks are (1) the increased weight of the rigid backrests over the sling systems, (2) discomfort when the user wants to perform non-mobility tasks, like dressing or relaxing (leaning back) , and (3) the inability to use the rigid shells on a folding-frame wheelchair. If these design shortcomings were mitigated, market penetration would increase substantially. We developed a Light-weight, Durable, Adjustable backrest (LWDAC) which addresses shortcomings (1) &(2) and was very well received by focus groups subjects. In this Phase II project, we will refine the LWDAC based on subjects'feedback, and introduce a quick-release mechanism to address shortcoming (3), which has already been developed for our other backrest system. PUBLIC HEALTH RELEVANCE: Despite the increased comfort and postural support that rigid wheelchair backrests provide, some users reject them because they restrict function during non-mobility tasks, like dressing or relaxing. To address these shortcomings, we have developed a Lightweight, Durable, Adjustable, Composite backrest system which allows the user to independently and easily adjust their backrest for all tasks.